The U.S. and other industrialized nations are producing large amounts of industrial and residential solid waste. Much of this waste is Municipal Solid Waste ("MSW") which is waste that is generally produced in or near large metropolitan areas. The overwhelming majority of MSW is deposited in landfills or treatment centers near the metropolitan areas. The landfill space in many metropolitan areas, however, is being depleted much faster than new landfill space is being made available. Moreover, many landfills that serve metropolitan areas are at or near capacity, so large waste producing cities are having to transport their waste to disposal sites located elsewhere.
The disposal sites for MSW are ideally located where land is inexpensive, opposition to disposing waste is minimal and there is enough space to acquire more land for expansion in the future. Such disposal sites are generally located in very remote areas that may be 350 to 2000 miles from the metropolitan centers. Current apparatuses and methods for hauling MSW, however, are inefficient and costly which limits the distance that the waste can be hauled away from the metropolitan centers.
Large amounts of industrial waste other than MSW also present environmental problems and recycling opportunities. Waste from pulp and paper mills, commonly called paper mill sludge, is an excellent fertilizer for tree farms. Yet, paper mill sludge is difficult to haul and tree farms are often located in mountainous regions far away from the mills. Another recyclable industrial waste is auto-fluff, which is a light-weight material that is often organic and useful as plant fertilizer. Auto-fluff is also difficult to haul because it is quite bulky and requires exceptionally large cargo holds to haul significant quantities. As with the MSW, current apparatuses and methods for hauling these materials are inefficient and costly.
One current method of waste disposal is to haul the waste in trucks from staging areas in the city to landfill sites in nearby areas. Hauling MSW in trucks is the most costly and limiting method of transporting MSW away from metropolitan centers because trucks have a relatively limited capacity and are expensive to operate compared to bulk hauling systems. Accordingly, since trucking MSW is expensive, hauling large quantities of MSW away from metropolitan centers to distant landfills in trucks is unfeasible for most cities.
A second apparatus and method of disposing of MSW is to use barges to haul it away from metropolitan centers. Barging MSW is also a costly method of transportation, and it is limited to hauling MSW to areas near deep water passageways. Barges are additionally limited because certain fluid wastes can cause catastrophic environmental damage if any such waste is spilled into the water. Accordingly, barging MSW away from metropolitan centers is also unfeasible for hauling MSW to remote disposal sites.
Another method and apparatus for hauling MSW is to use intermodal containers on the front haul leg of a dedicated train route. Generally, a dedicated train route hauls a certain type of material in one direction (the front haul leg), and then the rail cars return empty in the other direction (the backhaul leg). Large rectangular intermodal containers are currently being stacked on flatbed rail cars in a "double-decker" configuration. The intermodal containers are filled with MSW at staging areas in metropolitan centers, and then the filled intermodal containers are hauled on trucks to a rail line. The filled intermodal containers are loaded onto flatbed rail cars and hauled to a disposal site, which is usually located a great distance away from a metropolitan center. Once the filled intermodal containers arrive at the disposal center, they are emptied, washed and reloaded onto the flatbed rail cars. The empty intermodal containers are then hauled back to the metropolitan centers where they are refilled with more MSW.
Although hauling MSW on the front haul leg of a dedicated train route is more cost-effective than using trucks or barges, entire trains must haul empty intermodal containers back to the metropolitan centers. The intermodal containers must be hauled back empty because MSW fouls the containers so that they cannot haul anything else. Moreover, using the front haul leg of a dedicated train route is the most expensive method of transporting materials by rail. Accordingly, hauling MSW over long distances on trains is generally still too expensive for many cities.
The cost of hauling materials by rail is greatly reduced by using the backhaul leg of a dedicated train route because railroad companies charge significantly less for using the backhaul leg. However, back hauling MSW on rail cars is currently unfeasible because the MSW will contaminate and foul the cars, which impairs the ability to use the cars for their intended purpose on the front haul leg. Therefore, a need exists for providing an apparatus and method for back hauling MSW on rail cars away from metropolitan centers that is efficient and cost-effective.